(a) Technical Field
The present invention relates to a silicon carbide Schottky-barrier diode device and a method for manufacturing the same. More particularly, it relates to a silicon carbide Schottky-barrier diode device, which reduces on-resistance through ion-implantation into a conduction region, and a method for manufacturing the same.
(b) Background Art
Recently, there has been a trend toward the development of application devices with a larger size and capacity, which has created a growing demand for semiconductor power devices having high breakdown voltage, high current, and high-speed switching characteristics.
Silicon carbide (SiC) power devices have better characteristics than silicon (Si) based power devices with respect to high breakdown voltage, high current, and high-speed switching characteristics.
In the case of a conventional art SiC Schottky barrier diode (SBD), a lightly-doped epitaxial layer with increased thickness is generally applied to improve the breakdown voltage of a device. However, this method is disadvantageous because when there is a thick, lightly-doped epitaxial layer in a conduction region, the resistance of the conduction region increases upon application of a forward voltage, thereby reducing the on-resistance characteristics of the device. As a result of the above limitation, the development of a SiC Schottky barrier diode (SBD) generally requires the application of a termination structure that displays improved withstanding voltage characteristics when used with an epitaxial layer of minimal thickness.
Accordingly, in a Schottky barrier diode, the on-resistance characteristics depend on the doping concentration and distance between a cathode electrode and a Schottky contact in which a current flows. Similarly, the breakdown voltage characteristics depend on the doping concentration and the distance between the cathode electrode and the Schottky contact. However, due to the electric field crowding effect, the on-resistance and breakdown voltage characteristics are primarily determined by the structure of the edge termination of a Schottky junction.
In view of the foregoing, there is a need in the art for SiC Schottky barrier diodes that do not suffer from the above disadvantages associated with conventional art SiC diodes.